Synthesis of (-)-fumagillin

Research was conducted to examine the synthesis of (-)-fumagillin. Fumagillin was prepared by conjugate addition to the enantiomerically pure enoene, followed by oxygenation of the derived enolate. A comparison of synthetic (-)-fumagillol with authentic material prepared from natural fumagillin was carried out. Results demonstrate that the in situ bromination/dehydrobromination protocol approach provides a potentially very flexible route from 1,1-disubstituted alkenes to cyclopentenes.